The behavior of salt precipitation in a single basin solar distiller at 75°C was investigated in a laboratory. Groundwater was used as the supply water with high concentrations of calcium and sulfates in ionic form. The variations in the calcium concentration in the brine over the time was measured using a Atomic Absorption Spectrophotometer. X-ray diffraction and scanning electron microscopy which analyzed the salt crystals. It was observed that the precipitation of salts occurred between the first and second hour of operating since as the amount of calcium in the brine diminished during this interval of time. Nevertheless, the concentration of calcium gradually increased in the brine during the third and fourth hour, suggesting that the remaining calcium did not precipitate out. From these preliminary results, it was concluded that the precipitation reaction is not isothermal but is rather driven by temperature gradients. The analysis of sediments shows CaCO{sub}3 as calcite and CaSO{sub}4 in anhydrite solid phase.
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